I have a feeling that with dual EP-600s in your awesome system that you prefer to listen to music at quite a higher level than I do - or at least you have the capability to do so. I'd sure like to have your setup in my HT!

I'm really after a minimalist, high quality system that looks elegant in my living room...

Actually, i don't really listen that loud.. With the dual 600's the room "fills" even at low volume...

I listen at about 1/2 of reference level, if that is any gauge of what volume i prefer. Granted, sometimes i do listen a bit louder.

Maybe, get an EP400 in a stock finish, it could be the black oak which is similar to your current sub.. Then you would still have the return/upgrade/addition option...? You could listen with the M22's with the 400 and decide if you want another pair or if you think you would be happy with M2's.

i think "moderate near-field listening" does not have much to do with room size, specially when the room is large.so, my instinct says it could be more than enough.near-field means less power demands.

near-field listening in a large room means you have more direct sound than reflected sound. how much more depends on the ratio between room acoustics/size relative to the distance from the front speakers to your ears.

it would be a good thing if you specify what this means:"I listen at about 1/2 of reference level"is it -10 or -6 or -3 dB?

I would order the 400 in the finish you want. That way you can see exactly how it looks in your room. I felt the same way about trying something in a non stock finish, but I was assured by the Axiom Mothership that it would be no problem to send it back.

Unfortunately I do not have an SPL Meter to give you a good answer on the levels that I'm using.

I realize that the following will not be of much value but here goes:

My 65 watt tube amp's volume knob is Minimum at 7 o'clock & Maximum around to 5 o'clock. I run it between 10 & 11 o'clock depending on the source material which is about 30 to 40% of max. For instance, today I played Spiro Gyra 'Good to Go-Go' SACD starting at 11 o'clock but had to get up & turn it down to 10. Throughout this SACD that is recorded at high levels, there were many passages where the kick drum gently jiggled my couch from 8' away.

With that SACD at the 11 o'clock setting, normal conversation in the listening area would be most difficult. At 10 o'clock conversation would require elevated voices but not to the yelling stage.

Roughly comparing it to my Denon in my HT, I would guess that I'm running the tube amp at -15 Db or so.

I luv my vintage F1000. It has given me great service & enjoyment over 2 decades. I bought it new for $1200 in 1992 which was a lot of money in those days. The Optimum 10 is the equivalent model today & is quite pricey with not much in the way of custom finishes.

Unfortunately Velodyne has gone mostly ID which makes them a PITA for us in Canada with cost & shipping. Only their lower end subs are available at places like Future Shop up here. In fact FS has the EQ-Max 10 incher on sale this week for $400 ($400 off) - which is a great deal - even less than the US price the last time that I checked. This sub is a newer version of the DLS-3750 that I have in my HT (I have 2) with an on board room EQ feature. I like mine as they perform well, make great stands for my M22s & they were great value for $300 apiece on clearance last year. You can get them in any colour as long as it is black.

I have no reservation in choosing an Axiom sub, especially for music...

Yeah, Tom; relative volume control settings are very little indication of loudness levels. Amplifiers have fixed gain, but different units have different designed gains. Also, some volume controls "open up" more quickly than others and let in more voltage to be subjected to the fixed gain at a lower setting. An amplifier that reaches the same loudness level at a lower setting than another may actually have less maximum power capability.

So yes, it's a good idea to have an SPL meter such as the Radio Shack digital model to see how loud you're actually listening and at least an approximation(from speaker sensitivity and listening distance)of the power being used.